mrc_cache: Move code for triggering memory training into mrc_cache

Currently the decision of whether or not to use mrc_cache in recovery
mode is made within the individual platforms' drivers (ie: fsp2.0,
fsp1.1, etc.).  As this is not platform specific, but uses common
vboot infrastructure, the code can be unified and moved into
mrc_cache.  The conditions are as follows:

  1.  If HAS_RECOVERY_MRC_CACHE, use mrc_cache data (unless retrain
      switch is true)
  2.  If !HAS_RECOVERY_MRC_CACHE && VBOOT_STARTS_IN_BOOTBLOCK, this
      means that memory training will occur after verified boot,
      meaning that mrc_cache will be filled with data from executing
      RW code.  So in this case, we never want to use the training
      data in the mrc_cache for recovery mode.
  3.  If !HAS_RECOVERY_MRC_CACHE && VBOOT_STARTS_IN_ROMSTAGE, this
      means that memory training happens before verfied boot, meaning
      that the mrc_cache data is generated by RO code, so it is safe
      to use for a recovery boot.
  4.  Any platform that does not use vboot should be unaffected.

Additionally, we have removed the
MRC_CLEAR_NORMAL_CACHE_ON_RECOVERY_RETRAIN config because the
mrc_cache driver takes care of invalidating the mrc_cache data for
normal mode.  If the platform:
  1.  !HAS_RECOVERY_MRC_CACHE, always invalidate mrc_cache data
  2.  HAS_RECOVERY_MRC_CACHE, only invalidate if retrain switch is set

BUG=b:150502246
BRANCH=None
TEST=1. run dut-control power_state:rec_force_mrc twice on lazor
        ensure that memory retraining happens both times
        run dut-control power_state:rec twice on lazor
        ensure that memory retraining happens only first time
     2. remove HAS_RECOVERY_MRC_CACHE from lazor Kconfig
        boot twice to ensure caching of memory training occurred
	on each boot.

Change-Id: I3875a7b4a4ba3c1aa8a3c1507b3993036a7155fc
Signed-off-by: Shelley Chen <shchen@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46855
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

2 files changed, 8 insertions, 9 deletions

diff --git a/src/northbridge/intel/haswell/raminit.c b/src/northbridge/intel/haswell/raminit.c
index 63d70f792f..290e402fcb 100644
--- a/src/northbridge/intel/haswell/raminit.c
+++ b/src/northbridge/intel/haswell/raminit.c
@@ -112,10 +112,11 @@ void sdram_initialize(struct pei_data *pei_data)
 
 	printk(BIOS_DEBUG, "Starting UEFI PEI System Agent\n");
 
-	/* Do not pass MRC data in for recovery mode boot, always pass it in for S3 resume */
-	if (!(CONFIG(HASWELL_VBOOT_IN_BOOTBLOCK) && vboot_recovery_mode_enabled())
-	    || pei_data->boot_mode == 2)
-		prepare_mrc_cache(pei_data);
+	/*
+	 * Always pass in mrc_cache data.  The driver will determine
+	 * whether to use the data or not.
+	 */
+	prepare_mrc_cache(pei_data);
 
 	/* If MRC data is not found, we cannot continue S3 resume */
 	if (pei_data->boot_mode == 2 && !pei_data->mrc_input) {
diff --git a/src/northbridge/intel/sandybridge/raminit_mrc.c b/src/northbridge/intel/sandybridge/raminit_mrc.c
index 444ecf8cc7..8df7d1b36a 100644
--- a/src/northbridge/intel/sandybridge/raminit_mrc.c
+++ b/src/northbridge/intel/sandybridge/raminit_mrc.c
@@ -133,12 +133,10 @@ void sdram_initialize(struct pei_data *pei_data)
 	printk(BIOS_DEBUG, "Starting UEFI PEI System Agent\n");
 
 	/*
-	 * Do not pass MRC data in for recovery mode boot,
-	 * Always pass it in for S3 resume.
+	 * Always pass in mrc_cache data.  The driver will determine
+	 * whether to use the data or not.
 	 */
-	if (!(CONFIG(SANDYBRIDGE_VBOOT_IN_BOOTBLOCK) && vboot_recovery_mode_enabled()) ||
-	    pei_data->boot_mode == 2)
-		prepare_mrc_cache(pei_data);
+	prepare_mrc_cache(pei_data);
 
 	/* If MRC data is not found we cannot continue S3 resume. */
 	if (pei_data->boot_mode == 2 && !pei_data->mrc_input) {